Single-cell transcriptomics reveals tumor-infiltrating B cell function after neoadjuvant pembrolizumab and chemotherapy in non-small cell lung cancer.

Non-small cell lung cancer (NSCLC) is the most pervasive lung cancer subtype. Recent studies have shown that immune checkpoint inhibitors achieved favorable clinical benefits in resectable NSCLC; however, the associated mechanism remains unclear. The role of T cells in antitumor immunity has received considerable attention, while the antitumor effects of tumor-infiltrating B cells (TIBs) in NSCLC remain poorly understood. Here, we conducted a single-cell RNA-seq analysis of immune cells isolated from 12 patients with IIIA NSCLC to investigate B cell subtypes and their functions following neoadjuvant chemoimmunotherapy. We confirmed the simultaneous existence of the four B cell subtypes. Among them, memory B cells were found to be associated with a positive therapeutic effect to neoadjuvant chemoimmunotherapy. Furthermore, we found that G Protein-Coupled Receptor 183 (GPR183) was most prevalent in memory B cells and associated with a positive therapeutic response. Multiplex immunofluorescence and flow cytometry experiments in an additional cohort of 22 treatment-naïve and 30 IIIA/IIIB NSCLC patients treated with neoadjuvant chemoimmunotherapy verified these findings. Overall, our analysis revealed the functions of TIBs and their potential effect on clinical treatment in NSCLC.

A midgut-specific lytic polysaccharide monooxygenase of Locusta migratoria is indispensable for the deconstruction of the peritrophic matrix.

Lytic polysaccharide monooxygenases (LPMOs) are important enzymes that boost the hydrolysis of recalcitrant polysaccharides, such as chitin. They are found extensively in different insect species and are classified as auxiliary activities family 15 (AA15) LPMOs (LPMO15). Some of them were identified from the insect midgut and proven to act on chitin. However, knowledge about their physiological roles during insect growth and development remains limited. Here, we found that midgut-specific LPMO15s are widely distributed in different insect orders, such as the orthopteran Locusta migratoria and the lepidopteran Bombyx mori. Using L. migratoria as a model insect, the function of midgut-specific LmLPMO15-3 during development was investigated. Double-stranded RNA-mediated downregulation of LmLPMO15-3 expression at the 4th or 5th instar nymph stage severely decreased the survival rate and resulted in lethal phenotypes. Hematoxylin and eosin staining results indicated that the deficient individuals exhibited incompletely digested peritrophic matrix (PM), which suggested that LmLPMO15-3 is essential for the deconstruction of the PM during molting. This study provides direct evidence of the physiological importance of a midgut-specific LPMO15 during insect development. As L. migratoria is one of the most destructive agricultural pests, LmLPMO15-3 is a potential target for pest management.

Collagen type 1 alpha 1 chain is a novel predictive biomarker of poor progression-free survival and chemoresistance in metastatic lung cancer.

Background: Collagen type 1 alpha 1 chain (COL1A1) is an extracellular matrix protein comprising two alpha 1 chains and one alpha 2 chain. Our previous study identified that COL1A1 is the key gene during the development and progression of lung adenocarcinoma by multi-omics analysis. However, the clinical significance of COL1A1 expression in lung cancer samples remains largely unknown. Here, we aimed to evaluate the level of COL1A1 in lung cancer samples and correlate its level with the clinical outcome. Methods: COL1A1 gene expression in lung cancer samples was analyzed using the Oncomine database (www.oncomine.org). A total of 308 lung cancer samples (208 formalin-fixed paraffin-embedded tissues and 100 blood samples) were assessed for protein expression of COL1A1. Immunohistochemistry staining and enzyme-linked immunosorbent assay were used to detect COL1A1 expression in tissues and serum, respectively. Results: We identified an elevation of COL1A1 in mRNA level and gene amplification in lung cancer tissues compared with normal lung tissues. High COL1A1 expression was observed in lung cancer tissues and serum (P < 0.05), it was significantly correlated with the peripheral type tumor, the larger diameter of the tumor, the occurrence of lymph node metastases and distant metastases, a higher TNM stage, and smoking (P < 0.05). High COL1A1 expression was associated with poor progression-free survival (PFS) and chemoresistance in lung cancer patients (P < 0.05). Multivariable Cox-regression analysis showed that COL1A1 expression was an independent prognostic factor (P < 0.05). Furthermore, the area under the receiver operating characteristic (AUC) curve was 0.909 for the combined COL1A1 and carcinoembryonic antigen (CEA) measurement. Conclusion: Our findings revealed that COL1A1 could be used as a novel diagnostic, prognostic, and chemoresistance biomarker of human lung cancer, and these results provide a potential therapeutic strategy for lung cancer patients.

A sensitive OFF-ON-OFF fluorescent probe for the cascade sensing of Al3+ and F- ions in aqueous media and living cells.

A simple Schiff-base ligand 2-hydroxy-1-naphthaldehyde semicarbazone (HNS) was synthesized and characterized. Based on the combined effect of inhibition of CH[double bond, length as m-dash]N isomerization and chelation-enhanced fluorescence (CHEF), HNS functions as a fluorescence "turn on" sensor for Al3+ in buffered aqueous media. Based on the strong affinity of Al3+ to F- ions, the in situ generated Al3+-HNS complex can also be utilized as an effective chemosensor for F- sensing by metal displacement approach, ensuing quenching of fluorescence by the reversible return of HNS from Al3+-HNS complex. Thus a method using a single probe for the detection of both Al3+ and F- ions is developed. The system exhibits high selectivity and sensitivity for Al3+ and F- ions and the detection limits were found to be as low as 6.75 × 10-8 M and 7.89 × 10-7 M, respectively. Furthermore, the practical applicability of this probe has been examined in living cells.

Correction: A sensitive OFF-ON-OFF fluorescent probe for the cascade sensing of Al3+ and F- ions in aqueous media and living cells.

[This corrects the article DOI: 10.1039/D0RA02848G.].

A colorimetric and ratiometric fluorescent probe for cyanide sensing in aqueous media and live cells.

A novel probe, 3-benzyl-2-(N-ethylcarbazole-3-vinyl)-benzothiazolium bromide (L), was synthesized and utilized for the specific detection of cyanide ions in neutral aqueous solution (HEPES buffer, pH 7.4). This probe displays a fast response through visible colorimetric and fluorogenic changes toward CN-, allowing for ratiometric sensing of cyanide in aqueous media. The ratiometric response is due to the breaking of the extensive π-conjugation and the intramolecular charge transfer (ICT) by the nucleophilic conjugation addition of cyanide to L, which is ascertained by NMR and ESI-MS analysis as well as density functional theory (DFT) calculations. The detection limit of CN- (3.39 × 10-7 M) is well below the limit recommended in the World Health Organization (WHO) guidelines for drinking water. Moreover, fluorescence co-localization studies demonstrate that L is a specific mitochondria-targeting fluorescent probe. As far as we are aware, compound L is the first mitochondria-targeting probe for cyanide detection and can be used for sensing CN- in living cells with dual channel ratiometric fluorescence imaging.

A phenolphthalein-based fluorescent probe for the sequential sensing of Al3+ and F- ions in aqueous medium and live cells.

A novel fluorescent probe, phenolphthalein­dialdehyde­(2­pyridyl) hydrazone (L), for sequentially detecting Al3+ and F- in almost 100% aqueous medium was successfully designed and synthesized. The probe offers two binding pockets for Al3+ to form a 1: 2 ligand/metal complex, leading to a significant fluorescence enhancement at 465 nm. Further, the in-situ formed L-Al complex acts as a secondary fluorescent chemosensor for F- by quenching the fluorescence of the complex with high selectivity. The detection limit for Al3+ and F- sensing is 2.28 nM and 0.13 µM, respectively, which are far below the World Health Organization (WHO) acceptable limits (7.41 µM for Al3+ ion and 79 µM for F-) in drinking water. The probe L was successfully applied to the detection of Al3+ and F- in cells using fluorescence microscopy.

An anthraquinone-based highly selective colorimetric and fluorometric sensor for sequential detection of Cu2+ and S2- with intracellular application.

2-(1-Amino-2-anthraquinonyliminomethyl)phenol (L) was facilely prepared as a spectroscopic probe by one step condensation between 1,2-diaminoanthraquinone and salicylaldehyde. The complexation of Cu2+ ions with L through 1 : 1 chelation resulted in a rapid pink-to-blue color change and significant quenching of the fluorescence at 604 nm in 1 : 1 THF : Tris-HCl buffer. The subsequent addition of S2- to this solution regenerated the initial spectrum of L as a result of L being released from the L-Cu2+ complex through a displacement mechanism, which makes L a dual-channel sensor for the naked eye detection of Cu2+ and S2- ions. The system has high selectivity toward Cu2+ and S2- ions even in the presence of other commonly coexisting ions and the detection limits were found to be 8.95 × 10-8 M and 1.36 × 10-7 M, respectively. Applicability of L to detect Cu2+ ions and S2- ions in tap water has been demonstrated. Paper strips were fabricated for the detection of Cu2+ and S2- by the colorimetric method. Furthermore, L has been successfully applied for cell imaging studies.